PROJECT SUMMARY/ABSTRACT With an estimated 30.2 million diagnosed and undiagnosed cases among adults (and another 84 million at risk), diabetes mellitus is one of the most prevalent chronic conditions and a leading cause of mortality in the US. Diabetes self-management education and training (DSME/T) is a recognized standard of care and provides patients with the requisite knowledge and skills to properly manage the condition, improve long-term health outcomes, and reduce health care spending. Yet, only (58%) of adults with diabetes report ever receiving formal DSME/T. Health insurance coverage that does not include benefits for DSME/T effectively imposes barriers to access for patients with limited financial resources. Many states have adopted legislation that requires public and/or private insurers to provide benefits for DSME/T; however, these requirements vary by state. It is unclear if these policies effectively improve access to DSME/T services. The objective of this proposal is to rigorously assess the impact of state-mandated health insurance benefits and reimbursement provisions on access to DSME/T among vulnerable, low-income patients with diabetes. Aim 1, quantify the change in the supply of DSME/T programs and certified providers (potential access) before and after the adoption of state-mandated benefits, tests the hypothesis that enactment of DSME/T insurance requirements is associated with an increase in the number of accredited DSME/T programs and certified providers within a state. This aim merges two novel datasets to provide a census of accredited DSME/T programs and certified providers and detail provisions of state benefit mandates over a period of ten years for 30 US states. Aim 2, quantify the impact of state-mandated insurance benefits on utilization (realized access) of DSME/T, tests the hypothesis that Medicaid insurance requirements increases utilization of DSME/T among Medicaid patients with diabetes. This aim will utilize an 9-year panel from twenty states included in the Medical Expenditure Panel Survey (MEPS) from 2008 to 2016. Aim 3, examine the association between patients? evaluated need for DSME/T and providers? referral orders for DSME/T (equitable access), will utilize electronic health record data (2010-2017) from a safety net population to test the hypothesis that patients? ?evaluated need? will increase the likelihood of receiving a DSME/T referral during a provider encounter. The proposed study is significant because it rigorously measures the impact of decades of state policies to address a ?priority condition? in the US. This study is innovative because it extends the evidence-base for diabetes care services through the use of novel data sources and a more sophisticated and policy-relevant measurement approach. Lastly, the proposed study effectively targets a high priority research area as defined by AHRQ: increasing the accessibility of healthcare.